## Function to set parameters

specify_parameters <- function(data, attribute, baseline, uniform, weights = NULL) {
  
  ## attribute lists
  parameters[[1]][[attribute]] <- levels(data[, attribute])
  
  ## baselines
  parameters[[2]][[attribute]] <- baseline
  
  ## marginal weights
  if (uniform == 1) {
    parameters[[3]][[attribute]] <- rep(1/length(parameters[[1]][[attribute]]), 
                                        length(parameters[[1]][[attribute]]))
  } else if (uniform == 0) {
    if (is.null(weights)) {
      print("Add a weight vector")
    } else {
      parameters[[3]][[attribute]] <- weights
    }
  } else {
    print("Uniform must be either 0 or 1.")
  }
  return(parameters)

}
